Entities Can Activate Pressure Plates Beside Them

Verification builds:
1.1.0.9 Retail

Summary:
Players and mobs can continue to activate pressure plates that they were previously standing on, if they drop off the edge of a block with a pressure plate on it, onto a piston extension. The player can step off, or be pushed off by a piston. This causes particular problems when making blaze farm funnels.

Steps to Reproduce:

1. Stand on the pressure plate on a raised block with a piston below (see screenshot)
2. Step off the edge slowly so you drop down right beside it
3. Test world attached so that this can be reproduced easily with pistons.

Observed Results:
The player is still activating the pressure plate.

Expected Results:
The pressure plate should release as soon as the player moves off it.

Screenshots/Videos attached: Yes

Notes:
Affects all types of pressure plate.